Zhaosheng He

A NOVEL POWER DIVIDER INTEGRATED WITH SIW AND DGS TECHNOLOGY

In this paper, a novel power divider integrated with substrate integrated waveguide (SIW) and defected ground structures (DGS) techniques is proposed to provide both power dividing and flltering functions. The SIW technique holds advantages of low proflle, low-lost, mass-production, easy fabrication and fully integration with planar circuits. By integrating with defected ground structures (DGS) technique, the size and cost of system can be efiectively reduced as the proposed power divider has a function of flltering which leads to reduction of one fllter. In order to verify the design approach, the proposed power divider with equal power divisions at the center frequency of 8.625GHz is fabricated and measured. The measured results demonstrate that the insertion loss is less than 1.2dB and the input return loss less than 16dB across the bandwidth of 1.4GHz (FBW is 16%). Moreover, the imbalances of the amplitude and phase are less than 0.3dB and 0.5 degree, respectively.

A Bandpass Filter Based on Half Mode Substrate Integrated Waveguide-to-Defected Ground Structure Cells

A half mode substrate integrated waveguide-to-defected ground structure (HMSIW-DGS) cell and its embedded form are proposed to miniaturize a bandpass filter. Both cells can purchase wideband frequency response and low insertion loss, as well as simple and easy fabrication. By cascading two of them according to design requirement, an X-band bandpass filter is designed and measured to meet compact size, low insertion loss, good return loss, second harmonic suppression, and linear phase.

A dual-band bandpass filter based on hybrid structure of substrate integrated waveguide and substrate integrated coaxial line

This paper presents a novel dual-band bandpass filter design based on hybrid structure of substrate integrated waveguide (SIW) and substrate integrated coaxial line (SICL), which is implemented by multi-layer printed circuit board process. The hybrid structure is realized by inserting the SICL resonator into the volume of the SIW cavity which enables the hybrid structure to support the co-transmission of two orthogonal transmission modes (TE10 in SIW and TEM in SICL). Exploiting the two transmission modes, filter with dual-band transmission characteristic can be realized with the upper frequency band determined by the coupled SIW cavity resonators and the lower frequency band controlled through the SICL resonators. Therefore, it brings great flexibility to design dual-band filters as the two passbands can be independently designed. In order to validate the proposed concept, a prototype for Ka-band local multipoint distribution service (LMDS) application is designed, fabricated and measured. Good agreements can be observed between the simulation and the measurement.

High selectivity tunable filtering power divider based on liquid crystal technology for microwave applications

Abstract A novel electrically tunable filtering power divider, based on liquid crystal (LC) technology, is designed and experimentally demonstrated in this paper. Using low-cost T-shaped inverted-microstrip structures integrated with two dual-mode open-loop resonators, the tunable power divider possesses bandpass-filtering frequency response. Moreover, transitions between inverted-microstrip and microstrip structures are specifically designed at the I/O ports for the self-packaged. The experimental results indicate that the central frequency can be tuned from 5.75 to 6.25 GHz, i.e. a relative tuning range of 8.3%, the 3-dB bandwidth is 6.8 ± 0.2% over the whole tuning range, and the maximum amplitude and phase imbalance are less than 0.8 dB and 2.5°, respectively. In addition, the proposed filtering power divider has three transmission zeros to improve the frequency selectivity.

Compact Bandpass Filter With High Selectivity Using Quarter-Mode Substrate Integrated Waveguide and Coplanar Waveguide

This letter presents a bandpass filter (BPF) based on a hybrid structure of quarter-mode substrate integrated waveguide (QMSIW) and coplanar waveguide (CPW). By incorporating two CPW resonators into two QMSIW resonators, the proposed filter obtains a high selectivity as the coupling between two CPW resonators is electric coupling, which helps to generate two transmission zeros. It also achieves compact layout as the embedded CPW resonators do not occupy extra area. In order to verify the design, a BPF with a center frequency of 8.7 GHz is fabricated and measured. The measured results show good agreement with the simulation results.

Novel multilayered substrate integrated waveguide narrowband filters for millimeter-wave 3D-MCM applications

Two novel bandpass filters (BPFs) with the same structure but different bandwidth are presented in this paper, they are based on multilayered printed circuit boards. In this work, an H-shape coupling slot is used to realize hybrid coupling, two substrate integrated waveguide (SIW) cavities in different layers are used for resonators, and the coplanar waveguide (CPW) in input and output port is used for feeding line. Due to the size and location of coupling slots changed, the second filter has narrower bandwidth and better suppression in stopband. With the 3D environment, the proposed filters overcome the drawback of large circuit size of traditional waveguide filters, and can be effectively used for 3D Multi Chip Model (3D-MCM) in Ka band. The simulated results show that the 3dB bandwidths are 1.88 GHz (FBW=5.4%) and 0.42 GHz (FBW=1.2%) respectively, and the insertion losses at central frequency are about 1.4 dB and 4.3 dB respectively. The circuit sizes of the two filters excluding feed lines are the same, which are about 0.5λg × 0.5λg, where Ig is the guided wavelength at the central frequency.

An X-band SIW-DGS bandpass filter with improved stopband performance

In this paper, a substrate integrated waveguide (SIW)-to-defected ground structure (DGS) bandpass filter with moderate fractional bandwidth and improved stopband performance is proposed and demonstrated for X-band radar application. Design considerations including the design approach are addressed. A third-order filter with a passband of 8.8-10.1 GHz is fabricated on a single-layer Rogers RT/Duroid 5880 substrate using linear arrays of metallized via-holes by a standard printed circuit board process. Measured results of the filter agree very well with the simulated results, showing the in-band insertion loss is 1.3 dB or less, and in-band return loss is better than 20dB, respectively. The stopband rejection in the frequency band of 12-22 GHz is better than 35 dB.

A wideband bandpass filter based on stepped impedance stubs and substrate integrated coaxial line

In this paper, a novel wideband bandpass filter is proposed using a stepped impedance stubs resonator and substrate integrated coaxial line (SICL) technology. The resonator produces three resonant frequencies and two attenuation poles near the edges of the passband, so a wide bandwidth and a sharp rejection can be obtained. A filter prototype with compact size is simulated and the results indicate that the proposed filter centered at 13.16 GHz is realized with a bandwidth of 28.3%. The filter features low insertion loss, wide stopband, and low crosstalk.

Design of compact bandpass filter based on quarter-mode substrate integrated waveguide with mixed coupling

In this paper, a compact bandpass filter using quarter-mode substrate integrated waveguide (QMSIW) cavities with mixed coupling is presented. The mixed coupling is realized by etching a coplanar waveguide(CPW) at the magnetic coupled neighborhood section of two cascaded QMSIW resonators, which introduces two transmission zeros at the lower and higher rejection band. The filter enjoys merits of good selectivity, miniaturized size and wide stop band. In order to verify the design concept, a bandpass filter with center frequency of 8.625GHz is fabricated and measured. The measured results show good agreement with the simulated results.

Design of planar narrow band millimetre-wave filter with wide stop-band

This paper presents a planar millimetre-wave (mmwave) band pass filter based on substrate integrated waveguide (SIW) and substrate integrated coaxial line (SICL) techniques. Four half wavelength mircrostrip resonators are imbedded in the SIW cavity to improve Q-factor. Due to the closed configuration which eliminates radiation loss, the filter presents a relatively low insertion loss. The proposed filter has a 3dB fractional bandwidth of 1.6% across frequencies from 29.8GHz to 30.3 GHz and 20dB rejection band from 30.7GHz to 58 GHz.